Deodoriser

ABSTRACT

A device that is adapted to add active to the water of a flushed toilet and fragrance to the air in its vicinity, comprising, in a single unit
         (a) water-soluble rim block comprising active;   (b) fragrance dispenser, and   (c) means for holding (a) and (b) in the path of flush water from a toilet bowl rim; characterised in that the fragrance dispenser comprises a container with an opening covered by a membrane having a thickness of from 0.05-1.0 mm and consisting essentially of a homogeneous mixture of 8 to 98 vol. % polyolefin having a molecular weight (weight-average) of at least 300,000, a standard load melt index of less than 0.1 and a reduced viscosity of not less than 4.0, 1 to 92 vol. % filler and 1 to 40 vol. % plasticizer, the fragrance dispenser being orientated such that the fragrance is permanently in contact with the membrane.

This description relates to devices for disinfecting and deodorising toilets.

One well-known way of deodorising and disinfecting toilet bowls is by hanging a device comprising a soluble block containing an active (typically one or more of a cleaning agent, a disinfectant and a fragrance) in a toilet bowl such that the flush water from the bowl rim washes over it and releases some active. These are generally known as “rim blocks”, which term shall hereinafter be used to describe them. Various iterations of the same idea have been used. For example, the block (usually held in a cage, and this refillable) has been replaced by an active-containing gel of natural or synthetic material, with the desired solubility/active leaching characteristics.

The rim blocks have enjoyed wide success, because they are cheap and convenient to use. However, it is also known that their fragrance performance is not as good as desired, especially near the end of the life of the block, when performance falls off sharply. Ideally, the fragrance should stay sufficiently strong until the rim block disappears or needs to be changed. No block currently on the market does this. There have been attempts to overcome the problem, such as combining the rim block with a polyolefin membrane-based air freshener. However, this type of membrane is known to have major selectivity issues leading to fragrance restrictions when fragrancing this sort of system. Another attempted solution was to combine the rim block with a fragranced gel, but here again there are technical drawbacks as these gels are not water-soluble (no end of life signal) and their olfactory performance falls off significantly before mid-life.

It has now been found that it is possible to make a block that can perform in this desirable fashion. There is therefore provided a device that is adapted to add active to the water of a flushed toilet and fragrance to the air in its vicinity, comprising, in a single unit

-   -   (a) water-soluble rim block comprising active;     -   (b) fragrance dispenser, and     -   (c) means for holding (a) and (b) in the path of flush water         from a toilet bowl rim; characterised in that the fragrance         dispenser comprises a container with an opening covered by a         membrane having a thickness of from 0.05-1.0 mm and consisting         essentially of a homogeneous mixture of 8 to 98 vol. %         polyolefin having a molecular weight (weight-average) of at         least 300,000, a standard load melt index of less than 0.1 and a         reduced viscosity of not less than 4.0, 1 to 92 vol. % filler         and 1 to 40 vol. % plasticizer, the fragrance dispenser being         orientated such that the fragrance is permanently in contact         with the membrane.

There is additionally provided a method for both deodorising water in a toilet bowl and providing fragrance in the bowl, comprising the location in the path of flush water of a device comprising both a water-soluble rim block and a fragrance dispenser, the fragrance dispenser comprising a membrane having a thickness of from 0.05-1.0 mm and consisting essentially of a homogeneous mixture of 8 to 98 vol. % polyolefin having a molecular weight (weight-average) of at least 300,000, a standard load melt index of less than 0.1 and a reduced viscosity of not less than 4.0, 1 to 92 vol. % filler and 1 to 40 vol. % plasticizer, the fragrance dispenser being orientated such that the fragrance is permanently in contact with the membrane.

The rim block is similar to known rim blocks, consisting typically of a cage of any suitable material and containing a block, either of a solid material, or a gel, also in solid form or in a membrane enclosure that allows contact with water. Typical gels are made of xanthan gum Carbopol, or cellulose derivatives. The block may contain any desirable active in a typical art-recognised concentration. Typical actives (more than one may be present) include cleaning agents, detergents and surfactants, fragrances, disinfectants, bactericides and malodour counteractants.

The fragrance dispenser may be any suitable container of any suitable material that does not affect or is not affected by fragrance. It may be, for example, plastics, metal, ceramic or composite material. Its dimensions are not narrowly critical, provided they permit both an adequate charge of fragrance and the ability to fit in a toilet bowl. It may be fitted to the block itself or to the cage holding the block. The factors determining the actual arrangement include whether the device is a once-only disposable device or a refillable device, but the skilled person can easily provide a suitable arrangement for any particular configuration.

The fragrance container has an opening that is covered by a membrane with which the fragrance is in permanent contact. This can be arranged in any convenient way. For example, the dispenser may include a porous wick, which contacts both liquid and membrane, and through which fragrance is conveyed to the membrane and thus to the atmosphere. However, in a particular embodiment, the liquid contacts the membrane directly. Again, this can be by any suitable arrangement, a typical one being a container having the form of a shallow cylinder, open at one end, the open end being closed with the membrane and the container being arranged such that the membrane is vertical. With the particular membranes involved here, it is possible to have the container upside-down, so that the membrane forms the floor of the container. The membrane may be attached to the container in any convenient manner, for example, by being adhered to it, or by being part of a screw-on lid.

The membrane consists essentially of a homogeneous mixture of 8 to 98 vol. % polyolefin having a molecular weight (weight-average) of at least 300,000, a standard load melt index of less than 0.1 and a reduced viscosity of not less than 4.0, from 1 to 92 (particularly from 10-30) vol. % filler and 1 to 40 vol. % plasticizer. Suitable fillers and plasticizers are known to the art. In this context, reference is made to U.S. Pat. No. 3,351,495. A particular filler is finely-divided silica (silicic acid). The average particle size (diameter) of the filler is the range from 0.01 to about 20 .mu.m (milliatomic mass unit times metre) the surface area of the filler being in the range from 30 to 950 m²/g, and particularly at least 100 m²/g. Other fillers that may be used include various mineral fillers, such as clays, zeolites and carbonates, and charcoal.

The membrane is particularly of 0.25-0.7 mm thickness, more particularly about 0.6 mm

Such membranes are known to the art, being used, for example, as battery separators. Commercial examples are sold by, for example, Daramic, Inc.

Membranes as hereinabove defined have a number of very useful characteristics. One is that they do not allow the passage of water through them. They are thus unaffected by water running over them when a toilet is operated. Another is that they allow the passage of alcohol-type fragrance materials. Many of the most common fragrance materials have alcohol functionality, for example, linalool and dihydromyrcenol, and other membranes do not readily allow these through. The result is that the desired olfactory effect of a carefully-formulated fragrance is not achieved, and perfumes for use with membranes previously use by the art (typically LLDPE/EVOH/ LLDPE laminates of about 50 to 100 micron thickness) had to be specifically formulated to allow for this. Moreover, the technical restrictions linked to this type of membrane do not allow the perfumers to create in all olfactive directions, for example, real performing lavender fragrances are impossible to create. The membranes hereinabove described will allow the passage of alcohol fragrance materials, and so there is no need specifically to formulate a fragrance for this use. An unusually wide spectrum of fragrances may therefore be used.

In addition, the membranes have the feature of colour change when the fragrance is exhausted, thus giving a convenient end-of-life indication.

In addition, the membranes hereinabove described are unaffected by water. Thus, the flow of flush water in a toilet bowl across the membrane has no effect on its performance. They do not absorb the water, so there is no risk of contamination of the fragrance in the container. The orientation of the membrane with respect to the flow of flush water is therefore not important and the membrane may be positioned in any desired orientation, depending on other practical or aesthetic considerations.

The means for holding the device in the path of flush water may be any convenient device. It is typically a hook, which hooks over the rim of a toilet bowl and which, at its other end, is attached to the device, the dimensions being such as to allow proper positioning. The hook may be integral with the device (for example, moulded with a plastics cage as one piece), or it may be a separate piece, able to be attached to the device when the latter is ready to be put into service. The appropriate selection of materials, dimensions and geometry are all within the ordinary skill of the art.

The devices hereinabove defined offer substantial advantages over existing products. They permit a prolonged effectiveness, which lasts throughout the service life of the device, plus the convenience of an end-of-life indication for the fragrance dispenser.

The device is now further defined with respect to the accompanying drawings, which depicts particular embodiments, and which are not intended to be in any way limiting.

FIG. 1 is a schematic transverse cross-section of a particular embodiment.

FIG. 2 is a schematic part transverse cross-section of a further particular embodiment.

In FIG. 1, a device generally indicated as 1 comprises a cage 2 in the form of a tray from which extends upwardly a support member 3, which ends in a hook member 4, adapted to 10 hook around a rim of a toilet bowl, the support member 3 being of such a length that the cage 2 lies in the path of flush water from the rim. That side of the cage 7 opposite to the support member is perforated, so that flush water can escape through it. The elements 2, 3, 4 and 7 are of a plastics material and are moulded in a single piece.

Within the tray are seated a toilet block 5 and a fragrance dispenser 6. The toilet block is a block of the type well known to the art, consisting of anionic and non-ionic surfactants, principally alkyl benzene sulphonates and ethoxylated fatty alcohols, fillers/builders, such as sodium sulphate and chelating agents to counter the effects of hardness in water. The fragrance content is 5% by weight of the block.

The fragrance dispenser 6 has the form of a shallow cylindrical dish of plastics material and contains 10 ml perfume. The membrane, which is bonded to the open face of the dish is Membrane DS2 drying sweat system (ex Daramic, Inc) of 1 mm thickness.

The dispenser 6 is filled with perfume and is seated in the cage 2 beside the block, such that the membrane is substantially vertical, and that the perfume within is in permanent contact therewith. The dispenser is dimensioned, so that it fits easily within the cage, but is located sufficiently firmly that it will not be dislodged by the flow of flush water.

In operation, the flush water flows into the tray and out again through the perforated side 7, taking with it cleaning materials from the block 5. When the water flow has subsided, the fragrance dispenser dispenses fragrance through the membrane and also through the perforated side 7, as depicted by the wavy lines in FIG. 1.

The membrane described has the characteristic of changing colour when the fragrance is exhausted. This provides am end-of-life signal, allowing for the replacement of the fragrance dispenser.

In FIG. 2, the members 3 and 4 are the same as in FIG. 1, but the tray 2 is divided into an upper portion 8 and a lower portion 9, the lower portion being located vertically below the upper portion when the device is positioned in a toilet bowl. A toilet block 5 resides in the upper portion and a fragrance dispenser 6 in the lower portion 9. A side 10 of the upper portion opposite the support member is perforated, the perforations extending to the boundary of the upper and lower portions. The lower portion also has a perforated face 11, this being located at the base of the lower portion 9, such that it faces downwards into the toilet bowl. In this case, the fragrance dispenser 6 is places such that the membrane lies against the perforated face 11.

The operation of the FIG. 2 device is similar to that of FIG. 1, except in this case fragrance emission is continuous, even when a flush is in progress. 

1. A device that is adapted to add active to the water of a flushed toilet and fragrance to the air in its vicinity, comprising, in a single unit (a) water-soluble rim block comprising active: (b) fragrance container, and (c) means for holding (a) and (b) in the path of flush water from a toilet howl rim: characterised in that the fragrance dispenser comprises a container with an opening covered by a membrane having a thickness of from 0.05-1.0 mm and consisting essentially of a homogeneous mixture of 8 to 98 vol. % polyolefin having a molecular weight (weight-average) of at least 300,000, a standard load melt index of less than 0.1 and a reduced viscosity of not less than 4.0, 1 to 92 vol. % filler and 1 to 40 vol. % plasticizer, the fragrance dispenser being orientated such that the fragrance is permanently in contact with the membrane.
 2. The device according to claim 1, in which the average particle size (diameter) of the tiller is the range from 0.01 to about 20 ∥.mu.m∥ μm, the surface area of the filler being in the range from 30 to 950 m²/g.
 3. The device according to claim 1, in which the filler is finely-divided silica (silicic acid).
 4. The device according to claim 1, in which the membrane is from 0.25-0.7 mm thick.
 5. The device according to claim 1, in which the fragrance comprises alcohol components.
 6. A method for both deodorising water in a toilet bowl and providing fragrance in the bowl, comprising locating in the path of flush water of a device comprising both a water-soluble rim block and a fragrance dispenser, the fragrance dispenser comprising a membrane having a thickness of from 0.05-1.0 mm and consisting essentially of a homogeneous mixture of 8 to 98 vol. % polyolefin having a molecular weight (weight-average) of at least 300,000, a standard load melt index of less than 0.1 and a reduced viscosity of not less than 4.0, 1 to 92 vol. % filler and 1 to 40 vol. % plasticizer, the fragrance dispenser being orientated such that the fragrance is permanently in contact with the membrane.
 7. The device according to claim
 2. wherein the surface area of the filler is at least 100 m²/g. 